Carburetor Synchronization - Honda Motorcycle Service Manual

CARBURETOR SYNCHRONIZATION
NOTE
.
Carburetor synchronization adjustment is required to ad-
just the throttle valve opening, and to synchronize the
vacuum in each carburetor's intake port, whenever 2 or
more carburetors are reassembled.
.
Synchronize the carburetors with the engine at normal
operating temperature, the transmission in neutral and
the motorcycle on its center stand.
Carburetor numbers match the cylinder number.
Remove the plugs from each cylinder head port and install the
vacuum gauge adapters.
If the motorcycle is equipped with an automatic fuel valve,
disconnect the vacuum tube from the intake manifold of the
carburetor, draw vacuum and pinch the tube with a clip as
shown.
Connect the vacuum gauge.
1 . Adjust the idle rpm to the specified idle speed.
Model Specific manual for the specification.)
1
PLUG
I
VACUUM TUBE
,
CLIP
2. Turn the synchronization adjusting screw so that the dif-
ference between the vacuum in the base carburetor's in-
take port and the vacuum in the other carburetor's intake
port is below the specification. (Refer to the Model Specific
manual for base carburetor, location of each synchroniza-
tion adjusting screw and difference in vacuum between the
carburetors.)
(Refer to the
3. Be sure that the synchronization is stable by snapping the
throttle grip several times.
VACUUM GAUGE
4. Repeat steps 1 through 3 for each carburetor
SYRICHHOhlZATIOh
ADJUST hG SCREWS
Date of Issue : March,
1995
2-1 6
o
HoNOA MOTOR CO.,LTD.
5. Snap the throttle grip several times and recheck the idle
speed and differences in vacuum between each carburetor.
, ,